It is not uncommon for a person to be ordered to adhere to a constraining order in which the person must stay a specific distance away from another person. Or, one can envision a scenario involving domestic violence, in which a person does not want to be in proximity of another person in order to avoid a conflict. With the widespread use of portable communications devices, however, such as cellular phones and local number portability features available in wireline systems (e.g., landline systems), a called party can no longer be sure about the location of a calling party.